CBSE NOTES CLASS 12 PHYSICS
CHAPTER 13 NUCLEUS
Rate of decay
The total decay rate R of a sample is the number of nuclei disintegrating per unit time.
We can therefore, write,
The decay rate of a sample is called activity. The SI unit for activity is Becquerel
Another unit of activity is curie.
1 curie = 1 Ci = 3.7×1010 decays per second = 3.7×1010 Bq